PE-backed leak investigation and self-performed waterproofing for Alexandria's historic commercial buildings, condominiums, offices, and parking structures — from the Old Town waterfront to Carlyle, Del Ray, Potomac Yard, and the West End.
Search for waterproofing in Alexandria and you'll find residential basement franchises — sump pumps, interior drains, crawl-space encapsulation. That toolkit was built for single-family houses, not for a King Street storefront with two centuries of brick above the sidewalk, a condominium podium at Carlyle, or an office building on the West End. Alexandria's commercial stock fails at the envelope, and it fails in ways this city makes uniquely hard: blocks near the Potomac sit on a high water table and see recurring tidal and storm flooding along the lower waterfront; Old Town's 18th- and 19th-century masonry depends on soft lime-based mortar and breathable brick that the wrong sealer or hard Portland repointing will destroy; and newer mixed-use buildings at Potomac Yard and Eisenhower Valley stack plaza decks, terraces, and green roofs directly over occupied space and parking.
That is exactly what OAK Builders' waterproofing division does. We are a Virginia Class A commercial general contractor headquartered in Falls Church — about 15 minutes up Route 7 — licensed and insured in Virginia, DC, and Maryland ($1M/$2M CGL), with a licensed structural engineer (PE) on the team. Our principal managed building-envelope rehabilitation programs for federal landmark buildings: exterior stone restoration and repointing at the National Building Museum, a building envelope study for OPM headquarters, and three phases of VDOT building-envelope rehabilitation. If your building is in Alexandria's historic districts, that is the standard of masonry care and documentation the Board of Architectural Review expects — and the kind we bring to every repointing and façade repair. Learn more about our historic property construction work.
Below-grade leaks into occupied lower levels, cellars, and parking garages — a chronic problem on waterfront blocks with a high water table; rising damp and saturated historic masonry in Old Town storefronts and rowhouse-scale commercial buildings; failed sealant joints and spalling façades on office and condominium towers; plaza deck, terrace, and balcony failures over habitable space at Carlyle, Potomac Yard, and Eisenhower Valley; expansion joints past their service life in parking structures; and chronic "roof leaks" that are actually flashing and roof-to-wall transition failures. We serve office buildings, historic commercial properties, condominium and HOA communities, retail, restaurants, institutional facilities, and parking structures throughout Alexandria — Old Town and the waterfront, Carlyle and Eisenhower East, Del Ray, Arlandria, Potomac Yard, Seminary Hill, and the Mark Center / Landmark West End.
Every Alexandria project follows the same six-step discipline: Assess (non-destructive moisture survey), Diagnose (controlled water testing to reproduce the leak), Design (a PE-backed repair with a line-item budget), Repair (our crews, phased for occupied buildings), Verify (post-repair water testing, documented), and Warrant (written workmanship warranty plus manufacturer system warranties). One contract, one accountable team — no investigator, designer, and installer pointing fingers at each other while your building keeps leaking. Read more about our full waterproofing systems and leak investigation service, or see how we approach recurring plaza deck leaks. We provide the same service in Arlington, VA, Fairfax, VA, and Bethesda, MD.
Call (826) CALL-OAK · 826-225-5625
Email info@oakcgc.com
or use our Request Estimate form.
Yes — and this is where the wrong contractor does real harm. Historic brick and lime-mortar walls need to breathe; sealing them with impermeable coatings or repointing with hard Portland cement traps moisture in the masonry and accelerates spalling. We use breathable treatments, compatible mortars, and repair details drawn from our principal's federal landmark restoration experience, and we document the work to the standard historic-district review boards expect.
Usually, but honestly: no membrane makes a below-grade space immune to major Potomac flood events. What we can fix is the everyday problem — groundwater and stormwater entering through failed below-grade waterproofing, cracks, penetrations, and dysfunctional drainage. We diagnose the actual water path with controlled testing, then design a repair matched to your building's real exposure, including drainage and flood-resilience measures where they make sense.
Yes. OAK Builders holds a Virginia Class A contractor license — the highest classification the Commonwealth issues — and is licensed and insured in Virginia, DC, and Maryland with $1M/$2M commercial general liability coverage. We are also a Virginia SWaM-certified small business (#828355), which matters for City of Alexandria and Commonwealth facility work.
Yes — occupied-building work is our specialty. For Alexandria that often means storefronts that must keep trading, condominiums where residents live above the work, and garages that can't fully close. Off-hours phasing, protection, pedestrian control, and coordination with property management are planned into the price up front, not discovered mid-job.
Assessment scheduled within days. Diagnosis you can trust, repair by the same team, water-tested before we leave.